A variety of injuries and deformities can cause damage to the posterior structures of a vertebrae, which include pedicles, laminae, and articular and spinous processes. To remedy the pain and incapacitation that can be associated with these injuries and deformities, one or more of the posterior vertebral structures may be surgically excised and replaced with a prosthetic device. For example, age, disease or injury, may cause an intervertebral disc to collapse and vertebral bodies to actually make contact. This in turn can cause increased load, wear, damage and resulting pain to one or more joints, such as the facet joints, or to the laminae which may result in the surgical removal of the facets, a facetectomy and/or the laminae, a laminectomy.
Current prosthetic devices used to replace structures removed in a facetectomy or laminectomy can result in either the immobilization at the facet joints or in the alternative extreme, hypermobility in the vertebral column. Therefore, a device is needed to restore more natural motion to the vertebral column after a facetectomy or laminectomy.